ôReap the Dark Tide" was the better tile for this. The story was the first to deal with population explosion, the environmental impact of humanity, and harvesting the sea to extend the food supply. The attention to detail given to the descriptions of the Convoy Culture and the degeneracy of the Land Culture is remarkable. The story certainly was ripe for expansion to novel length, but was written in 1958, the year of Kornbluth's death.
The Captain of a ship must violate centuries old tradition to save his crew. Centuries earlier, to ease population pressures, large numbers of people set out in great ships upon the sea. They take their living wholly from the sea, sailing east to west and back to east, from 10 miles of one coast to ten miles of the other.
Because all of their sustenance comes from the sea, they are dependent upon the harvest of their nets for food and for raw materials with which to manufacture all their goods. The metals of the hulls and nets is irreplaceable. To lose a net means death by slow starvation for a crew. The rest of the Convoy hasn't enough to spare.
The ship is part of one of a number of convoys. The Convoys have over-harvested their grounds to the point where only plankton and krill are plentiful. These are harvested twice a year in spring and fall.
The Fleet has been at sea for centuries, and have over-fished their ranges. They are down to harvesting plankton. The Charter has gone from a social compact to holy writ in the minds of the rank and file, and traditional approaches, though failing, carry the force of absolute edicts.After the end of one harvest, a sudden squall destroys the net. The traditional options are are mass suicide and death by cannibalism. Not only will no help come forth from the rest of the Convoy, the ship is exiled from the Fleet. They set of without so much as a good luck or a fare-the-well.
According to the Compact that established the convoys, The quote has been inculcated into the very fiber of every member of the crew's being for so long that it is taking on the nature of Holy Writ. The notion of seeking succour from the land is very nearly sacrilegious. Unwilling to accept death by starvation of death by civil war culminating in cannibalism, the Captain decides to see what the Land may hold in store for them.
They make landfall in New York Harbor. The Captain places his exec in command of the ship and leads a party ashore. Once landed, they find that overpopulation is no longer a problem there. A religious fruitcake has arisen and spread a new religion across the Land. The population has been dropping rapidly, because having more than one child [[? check on this ]] is a sin punishable by death. The permeating death cult is also severely crippled in its attitudes towards sex and the human body. This comes in handy after the shore party is surrounded and cones under attack The shore party returns home.